Common Weakness Enumeration

CWE-416

Weakness Allowed

Use After Free

Abstraction: Variant · Status: Stable

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Mapping guidance

This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.

Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Relationships and members
ChildOf: CWE-825 · View CWE-1000
ChildOf: CWE-672 · View CWE-1003
ChildOf: CWE-672 · View CWE-1305
ChildOf: CWE-672 · View CWE-1340
CanPrecede: CWE-120 · View CWE-1000
CanPrecede: CWE-123 · View CWE-1000
Modes of introduction
Implementation
Detection methods

Fuzzing

Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.

Effectiveness: High

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)

Effectiveness: High

Automated Dynamic Analysis

Use tools that are integrated during compilation to insert runtime error-checking mechanisms related to memory safety errors, such as AddressSanitizer (ASan) for C/C++ [REF-1518].

Effectiveness: Moderate

Crafted inputs are necessary to reach the code containing the error, such as generated by fuzzers. Also, these tools may reduce performance, and they only report the error condition - not the original mistake that led to the error.

Content history
Submission: 7 Pernicious Kingdoms · 2006-07-19 · CWE Draft 3
Contribution: Anonymous External Contributor · 2022-06-28 · CWE 4.9

Suggested rephrase for extended description

Contribution: participants in the CWE ICS/OT SIG 62443 Mapping Fall Workshop · 2023-11-14 · CWE 4.14

Contributed or reviewed taxonomy mappings for ISA/IEC 62443

Contribution: Abhi Balakrishnan · 2024-02-29 · CWE 4.15

Provided diagram to improve CWE usability

Modification: Eric Dalci · Cigital · 2008-07-01 · CWE 1.0

updated Potential_Mitigations, Time_of_Introduction

Modification: · KDM Analytics · 2008-08-01 · CWE 1.0

added/updated white box definitions

Modification: CWE Content Team · MITRE · 2008-09-08 · CWE 1.0

updated Applicable_Platforms, Common_Consequences, Relationships, Observed_Example, Other_Notes, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2008-11-24 · CWE 1.1

updated Relationships, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2009-03-10 · CWE 1.3

updated Demonstrative_Examples

Modification: CWE Content Team · MITRE · 2009-05-27 · CWE 1.4

updated Demonstrative_Examples

Modification: CWE Content Team · MITRE · 2009-10-29 · CWE 1.6

updated Common_Consequences

Modification: CWE Content Team · MITRE · 2010-02-16 · CWE 1.8

updated Relationships

Modification: CWE Content Team · MITRE · 2010-06-21 · CWE 1.9

updated Potential_Mitigations

Modification: CWE Content Team · MITRE · 2010-09-27 · CWE 1.10

updated Observed_Examples, Relationships

Modification: CWE Content Team · MITRE · 2010-12-13 · CWE 1.11

updated Alternate_Terms, Common_Consequences, Description, Observed_Examples, Other_Notes, Potential_Mitigations, Relationships

Modification: CWE Content Team · MITRE · 2011-03-29 · CWE 1.12

updated Description

Modification: CWE Content Team · MITRE · 2011-06-01 · CWE 1.13

updated Common_Consequences

Modification: CWE Content Team · MITRE · 2011-06-27 · CWE 2.0

updated Demonstrative_Examples

Modification: CWE Content Team · MITRE · 2011-09-13 · CWE 2.1

updated Relationships, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2012-05-11 · CWE 2.2

updated References, Relationships

Modification: CWE Content Team · MITRE · 2014-07-30 · CWE 2.8

updated Relationships, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2015-12-07 · CWE 2.9

updated Relationships

Modification: CWE Content Team · MITRE · 2017-11-08 · CWE 3.0

updated Demonstrative_Examples, Relationships, Taxonomy_Mappings, White_Box_Definitions

Modification: CWE Content Team · MITRE · 2019-01-03 · CWE 3.2

updated Relationships

Modification: CWE Content Team · MITRE · 2019-06-20 · CWE 3.3

updated Relationships, Type

Modification: CWE Content Team · MITRE · 2019-09-19 · CWE 3.4

updated Relationships

Modification: CWE Content Team · MITRE · 2020-02-24 · CWE 4.0

updated References, Relationships, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2020-06-25 · CWE 4.1

updated Relationships

Modification: CWE Content Team · MITRE · 2020-08-20 · CWE 4.2

updated Relationships

Modification: CWE Content Team · MITRE · 2020-12-10 · CWE 4.3

updated Relationships

Modification: CWE Content Team · MITRE · 2021-07-20 · CWE 4.5

updated Relationships

Modification: CWE Content Team · MITRE · 2022-06-28 · CWE 4.8

updated Observed_Examples, Relationships

Modification: CWE Content Team · MITRE · 2022-10-13 · CWE 4.9

updated Description, Relationships, Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2023-04-27 · CWE 4.11

updated Detection_Factors, Relationships, Time_of_Introduction

Modification: CWE Content Team · MITRE · 2023-06-29 · CWE 4.12

updated Mapping_Notes, Relationships

Modification: CWE Content Team · MITRE · 2023-10-26 · CWE 4.13

updated Observed_Examples

Modification: CWE Content Team · MITRE · 2024-02-29 · CWE 4.14

updated Taxonomy_Mappings

Modification: CWE Content Team · MITRE · 2024-07-16 · CWE 4.15

updated Alternate_Terms, Common_Consequences, Description, Diagram, Potential_Mitigations, Relationships, Weakness_Ordinalities

Modification: CWE Content Team · MITRE · 2024-11-19 · CWE 4.16

updated Relationships

Modification: CWE Content Team · MITRE · 2025-04-03 · CWE 4.17

updated Observed_Examples

Modification: CWE Content Team · MITRE · 2025-09-09 · CWE 4.18

updated Functional_Areas

Modification: CWE Content Team · MITRE · 2025-12-11 · CWE 4.19

updated Applicable_Platforms, Detection_Factors, References, Relationships

Modification: CWE Content Team · MITRE · 2026-04-30 · CWE 4.20

updated Common_Consequences, Observed_Examples

Modification: CWE Content Team · MITRE · 2026-10-28 · CWE 5.0

updated Observed_Examples, References

12544 vulnerabilities reference this CWE, most recent first.

GHSA-R445-3FV9-V4HX

Vulnerability from github – Published: 2026-07-30 03:31 – Updated: 2026-07-30 18:31
VLAI
Details

Use after free in ANGLE in Google Chrome prior to 151.0.7922.72 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: High)

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-17704"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-30T01:16:32Z",
    "severity": "CRITICAL"
  },
  "details": "Use after free in ANGLE in Google Chrome prior to 151.0.7922.72 allowed a remote attacker who had compromised the renderer process to potentially perform a sandbox escape via a crafted HTML page. (Chromium security severity: High)",
  "id": "GHSA-r445-3fv9-v4hx",
  "modified": "2026-07-30T18:31:27Z",
  "published": "2026-07-30T03:31:10Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-17704"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2026/07/stable-channel-update-for-desktop_0887107924.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/519259107"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R454-8J2H-FWQP

Vulnerability from github – Published: 2022-05-24 17:34 – Updated: 2023-02-13 00:31
VLAI
Details

In Xpdf 4.02, SplashOutputDev::endType3Char(GfxState *state) SplashOutputDev.cc:3079 is trying to use the freed t3GlyphStack->cache, which causes an heap-use-after-free problem. The codes of a previous fix for nested Type 3 characters wasn't correctly handling the case where a Type 3 char referred to another char in the same Type 3 font.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-25725"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-11-21T06:15:00Z",
    "severity": "MODERATE"
  },
  "details": "In Xpdf 4.02, SplashOutputDev::endType3Char(GfxState *state) SplashOutputDev.cc:3079 is trying to use the freed `t3GlyphStack-\u003ecache`, which causes an `heap-use-after-free` problem. The codes of a previous fix for nested Type 3 characters wasn\u0027t correctly handling the case where a Type 3 char referred to another char in the same Type 3 font.",
  "id": "GHSA-r454-8j2h-fwqp",
  "modified": "2023-02-13T00:31:19Z",
  "published": "2022-05-24T17:34:38Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-25725"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-25725"
    },
    {
      "type": "WEB",
      "url": "https://forum.xpdfreader.com/viewtopic.php?f=3\u0026t=41915"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4ZUU5QG6SSVRTKZTR3A72LDRVZETEI63"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VLOYVJSM54IL6I5RY4QTJGRS7PIEG44X"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4ZUU5QG6SSVRTKZTR3A72LDRVZETEI63"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/VLOYVJSM54IL6I5RY4QTJGRS7PIEG44X"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R45G-G88H-X98P

Vulnerability from github – Published: 2026-10-21 00:32 – Updated: 2026-10-21 00:32
VLAI
Details

Improper input validation in Views in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-113316"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-20T22:19:25Z",
    "severity": "HIGH"
  },
  "details": "Improper input validation in Views in Google Chrome prior to 156.0.8078.47 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)",
  "id": "GHSA-r45g-g88h-x98p",
  "modified": "2026-10-21T00:32:51Z",
  "published": "2026-10-21T00:32:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-113316"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2026/10/stable-channel-update-for-desktop_02018666648.html"
    },
    {
      "type": "WEB",
      "url": "https://issues.chromium.org/issues/553140050"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R46G-2XPJ-55MC

Vulnerability from github – Published: 2022-05-24 17:24 – Updated: 2023-01-27 18:30
VLAI
Details

Use after free in speech in Google Chrome prior to 83.0.4103.106 allowed a remote attacker to potentially perform a sandbox escape via a crafted HTML page.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-6505"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-07-22T17:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Use after free in speech in Google Chrome prior to 83.0.4103.106 allowed a remote attacker to potentially perform a sandbox escape via a crafted HTML page.",
  "id": "GHSA-r46g-2xpj-55mc",
  "modified": "2023-01-27T18:30:32Z",
  "published": "2022-05-24T17:24:04Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-6505"
    },
    {
      "type": "WEB",
      "url": "https://chromereleases.googleblog.com/2020/06/stable-channel-update-for-desktop_15.html"
    },
    {
      "type": "WEB",
      "url": "https://crbug.com/1081350"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202007-08"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R476-WGFV-FMG6

Vulnerability from github – Published: 2022-05-24 16:59 – Updated: 2022-05-24 16:59
VLAI
Details

Adobe Acrobat and Reader versions , 2019.012.20040 and earlier, 2017.011.30148 and earlier, 2017.011.30148 and earlier, 2015.006.30503 and earlier, and 2015.006.30503 and earlier have an use after free vulnerability. Successful exploitation could lead to arbitrary code execution .

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2019-8223"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-10-17T21:15:00Z",
    "severity": "HIGH"
  },
  "details": "Adobe Acrobat and Reader versions , 2019.012.20040 and earlier, 2017.011.30148 and earlier, 2017.011.30148 and earlier, 2015.006.30503 and earlier, and 2015.006.30503 and earlier have an use after free vulnerability. Successful exploitation could lead to arbitrary code execution .",
  "id": "GHSA-r476-wgfv-fmg6",
  "modified": "2022-05-24T16:59:25Z",
  "published": "2022-05-24T16:59:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-8223"
    },
    {
      "type": "WEB",
      "url": "https://helpx.adobe.com/security/products/acrobat/apsb19-49.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-R484-PM6M-49RR

Vulnerability from github – Published: 2022-02-19 00:01 – Updated: 2022-02-26 00:00
VLAI
Details

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Bentley MicroStation CONNECT 10.16.0.80. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of JT files. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-15382.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2021-46588"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-02-18T20:15:00Z",
    "severity": "HIGH"
  },
  "details": "This vulnerability allows remote attackers to execute arbitrary code on affected installations of Bentley MicroStation CONNECT 10.16.0.80. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of JT files. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-15382.",
  "id": "GHSA-r484-pm6m-49rr",
  "modified": "2022-02-26T00:00:53Z",
  "published": "2022-02-19T00:01:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-46588"
    },
    {
      "type": "WEB",
      "url": "https://www.bentley.com/en/common-vulnerability-exposure/BE-2021-0005"
    },
    {
      "type": "WEB",
      "url": "https://www.zerodayinitiative.com/advisories/ZDI-22-175"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-R486-F9Q2-52QV

Vulnerability from github – Published: 2022-05-24 17:42 – Updated: 2022-05-24 17:42
VLAI
Details

Use after free in some Intel(R) Graphics Drivers before version 15.33.51.5146 may allow an authenticated user to potentially enable denial of service via local access.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-12361"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-02-17T14:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Use after free in some Intel(R) Graphics Drivers before version 15.33.51.5146 may allow an authenticated user to potentially enable denial of service via local access.",
  "id": "GHSA-r486-f9q2-52qv",
  "modified": "2022-05-24T17:42:24Z",
  "published": "2022-05-24T17:42:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-12361"
    },
    {
      "type": "WEB",
      "url": "https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00438.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-R49G-24WR-G2H5

Vulnerability from github – Published: 2022-05-14 00:53 – Updated: 2022-05-14 00:53
VLAI
Details

Adobe Acrobat and Reader 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier versions have a Use-after-free vulnerability. Successful exploitation could lead to arbitrary code execution in the context of the current user.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2018-12770"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2018-07-20T19:29:00Z",
    "severity": "HIGH"
  },
  "details": "Adobe Acrobat and Reader 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier versions have a Use-after-free vulnerability. Successful exploitation could lead to arbitrary code execution in the context of the current user.",
  "id": "GHSA-r49g-24wr-g2h5",
  "modified": "2022-05-14T00:53:02Z",
  "published": "2022-05-14T00:53:02Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-12770"
    },
    {
      "type": "WEB",
      "url": "https://helpx.adobe.com/security/products/acrobat/apsb18-21.html"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/104701"
    },
    {
      "type": "WEB",
      "url": "http://www.securitytracker.com/id/1041250"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R4C4-PXX8-R386

Vulnerability from github – Published: 2023-03-06 21:30 – Updated: 2023-03-13 18:30
VLAI
Details

An arbitrary file upload vulnerability in the camera_upload.php component of PMB v7.4.6 allows attackers to execute arbitrary code via a crafted image file.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-24734"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-03-06T21:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "An arbitrary file upload vulnerability in the camera_upload.php component of PMB v7.4.6 allows attackers to execute arbitrary code via a crafted image file.",
  "id": "GHSA-r4c4-pxx8-r386",
  "modified": "2023-03-13T18:30:43Z",
  "published": "2023-03-06T21:30:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-24734"
    },
    {
      "type": "WEB",
      "url": "https://github.com/AetherBlack/CVE/tree/main/PMB"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-R4CC-8GXC-2CXH

Vulnerability from github – Published: 2026-07-01 15:35 – Updated: 2026-07-18 09:32
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

fhandle: fix UAF due to unlocked ->mnt_ns read in may_decode_fh()

may_decode_fh() accesses mount::mnt_ns without holding any locks; that means the mount can concurrently be unmounted, and the mnt_namespace can concurrently be freed after an RCU grace period.

This race can happens as follows, assuming that the mount point was created by open_tree(..., OPEN_TREE_CLONE):

thread 1 thread 2 RCU __do_sys_open_by_handle_at do_handle_open handle_to_path may_decode_fh is_mounted [mount::mnt_ns access] [mount::mnt_ns access] __do_sys_close fput_close_sync __fput dissolve_on_fput umount_tree class_namespace_excl_destructor namespace_unlock free_mnt_ns mnt_ns_tree_remove call_rcu(mnt_ns_release_rcu) mnt_ns_release_rcu mnt_ns_release kfree [mnt_namespace::user_ns access] UAF

Fix it by taking rcu_read_lock() around the mount::mnt_ns access, like in __prepend_path(). Additionally, document the semantics of mount::mnt_ns, and use WRITE_ONCE() for writers that can race with lockless readers.

This bug is unreachable unless one of the following is set:

  • CONFIG_PREEMPTION
  • CONFIG_RCU_STRICT_GRACE_PERIOD

because it requires an RCU grace period to happen during a syscall without an explicit preemption.

This doesn't seem to have interesting security impact; worst-case, it could leak the result of an integer comparison to userspace (from the level check in cap_capable()), cause an endless loop, or crash the kernel by dereferencing an invalid address.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-53341"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-416"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-01T14:16:42Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nfhandle: fix UAF due to unlocked -\u003emnt_ns read in may_decode_fh()\n\nmay_decode_fh() accesses mount::mnt_ns without holding any locks; that\nmeans the mount can concurrently be unmounted, and the mnt_namespace can\nconcurrently be freed after an RCU grace period.\n\nThis race can happens as follows, assuming that the mount point was\ncreated by open_tree(..., OPEN_TREE_CLONE):\n\nthread 1            thread 2            RCU\n                    __do_sys_open_by_handle_at\n                      do_handle_open\n                        handle_to_path\n                          may_decode_fh\n                            is_mounted\n                              [mount::mnt_ns access]\n                            [mount::mnt_ns access]\n__do_sys_close\n  fput_close_sync\n    __fput\n      dissolve_on_fput\n        umount_tree\n        class_namespace_excl_destructor\n          namespace_unlock\n            free_mnt_ns\n              mnt_ns_tree_remove\n                call_rcu(mnt_ns_release_rcu)\n                                        mnt_ns_release_rcu\n                                          mnt_ns_release\n                                            kfree\n                            [mnt_namespace::user_ns access] **UAF**\n\nFix it by taking rcu_read_lock() around the mount::mnt_ns access, like\nin __prepend_path().\nAdditionally, document the semantics of mount::mnt_ns, and use WRITE_ONCE()\nfor writers that can race with lockless readers.\n\nThis bug is unreachable unless one of the following is set:\n\n - CONFIG_PREEMPTION\n - CONFIG_RCU_STRICT_GRACE_PERIOD\n\nbecause it requires an RCU grace period to happen during a syscall without\nan explicit preemption.\n\nThis doesn\u0027t seem to have interesting security impact; worst-case, it could\nleak the result of an integer comparison to userspace (from the level\ncheck in cap_capable()), cause an endless loop, or crash the kernel by\ndereferencing an invalid address.",
  "id": "GHSA-r4cc-8gxc-2cxh",
  "modified": "2026-07-18T09:32:16Z",
  "published": "2026-07-01T15:35:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53341"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/15ea8dc42a02259d49dee38a658d40f60fcd75ed"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/32138633e51e6db59e474765cf93268c92b42888"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/40ab6644b99685755f740b872c00ef40d9aa870e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a8ed2c29fcfdac78db96c9da4e659c8a513f2a94"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Architecture and Design

Strategy: Language Selection

Choose a language that provides automatic memory management.

Mitigation
Implementation

Strategy: Attack Surface Reduction

When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

No CAPEC attack patterns related to this CWE.